Understanding the presence, abundance, distribution, and population dynamics of micro-organisms that occur in aquatic environments requires frequent collection of discrete water samples at many locations and depths. Identification and enumeration of particular micro-organisms within those samples typically relies on laboratory-based methods that employ light and/or electron microscopy, and perhaps DNA, lectin, or antibody probes to reveal target species. Collecting appropriate samples over relatively large spatial and temporal scales (e.g., several square miles; months to years) is limited by the frequency one can spend visiting a particular location, and the absolute amount of time one can occupy that location. Similarly, providing quantitative measures of the abundance of a wide variety of micro-organisms that may inhabit those locations is restricted by the time and labor necessary for sample processing. In sharp contrast, many physical, chemical and gross biological properties of the water column may be determined in real-time using a variety of air borne, shipboard, moored and/or drifting sensor arrays. The disparity between the time required to gather and interpret physical and chemical measurements versus the effort to identify and enumerate particular micro-organisms in the same parcel of water, hampers the ability to generate synoptic views of the distribution and abundance of those species in an environmentally relevant context. This in turn impedes the ability to study, either in an applied or academic setting, a wide range of biological phenomena that is occurring at the single cell level, especially within a dynamic aqueous environment.
Molecular probe assays (DNA, PNA (peptic nucleic acid), lectin, or antibody) offer one means to speed and ease the detection and quantification of an enormous variety of organisms, as well the particular genes they harbor and express. However, such applications are presently hindered by the need for highly repetitive operations that demand trained personnel and specialized laboratory facilities. These requirements severely restrict the utilization of molecular probes for real-time ecological studies because the rate of sample processing is inherently limited and application of the technology outside of a laboratory setting is difficult, or more often impossible. U.S. Pat. No. 5,341,834, which is hereby incorporated by reference, discloses a multiport valve for a water transfer system for passing water drawn by a pump through multiple collectors. However, U.S. Pat. No. 5,341,834 discloses no information regarding the use of molecular probes for real-time detection of microorganisms in those samples.
Therefore, novel instrumentation is required if the analytical potential of molecular probe-based assays is to be merged in a synergistic fashion with existing and future capabilities of sensors that measure chemical and physical properties of aqueous environments. For environmental application, such an instrumentation package suitable for detection of micro-organisms should be portable, relatively simple to use, capable of autonomous operation in situ and have the capacity for real-time data transmission. To the best of our knowledge, instrumentation of this class does not exist.